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We aimed to investigate the mechanism underlying the roles of miRNA-377, Cystathionine-β-synthase (CBS), and hydrogen sulfide (H2S) in the development of hypoxic-ischemic encephalopathy (HIE). We investigated the relationship between CBS, H2S, and miR-377 in both humans with HIE and animals with hypoxic-ischemic insult. An animal model of fetal rats with hypoxic-ischemic brain injury was established, and the fetal rats were randomly assigned to control and hypoxic-ischemic groups for 15 min (mild) and 30 min (moderate) groups. Human samples were collected from children diagnosed with HIE. Healthy or non-neurological disease children were selected as the control group. Hematoxylin–eosin (HE) staining, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot were used to conduct this study. Hypoxia–ischemia induced pathological alterations in brain tissue changes were more severe in groups with severe hypoxic insult. miRNA-377 expression levels were upregulated in brain tissue and serum of fetal rats and human samples with HIE compared to controls. Conversely, CBS and H2S expression levels were significantly decreased in both human and animal samples compared to controls. Our findings suggest that CBS is a target gene of miR-377 which may contribute to the development of HIE by regulating CBS/H2S. H2S has a protective effect against hypoxic damage in brain tissue. The study provides new insights into the potential mechanisms underlying the protective role of H2S in hypoxic brain damage and may contribute to the development of novel therapies for HIE. [ABSTRACT FROM AUTHOR]

Atherosclerosis (AS) is one of the most common and important vascular diseases. It is believed that the abnormal expression of circular RNAs (circRNAs) plays an important role in AS. Hence, we investigate the function and mechanism of circ-C16orf62 in AS development. In this study, oxidized low-density lipoprotein (ox-LDL)-treated human macrophages (THP-1) were used as pathological conditions of AS in vitro. The expression of circ-C16orf62, miR-377 and Ras-related protein (RAB22A) mRNA was detected by real-time quantitative polymerase chain reaction (RT-qPCR) or western blot. Cell viability or cell apoptosis was assessed by cell counting kit-8 (CCK-8) assay or flow cytometry assay. The releases of proinflammatory factors were investigated using enzyme-linked immunosorbent assay (ELISA). The production of malondialdehyde (MDA) and superoxide dismutase (SOD) was examined to assess oxidative stress. Total cholesterol (T-CHO) level was detected, and cholesterol efflux level was tested using a liquid scintillation counter. The putative relationship between miR-377 and circ-C16orf62 or RAB22A was verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. circ-C16orf62 expression was elevated in AS serum samples and ox-LDL-treated THP-1 cells. Apoptosis, inflammation, oxidative stress and cholesterol accumulation induced by ox-LDL were suppressed by circ-C16orf62 knockdown. Circ-C16orf62 could bind to miR-377 and thus increased the expression level of RAB22A. Rescued experiments showed that circ-C16orf62 knockdown alleviated ox-LDL-induced THP-1 cell injuries by increasing miR-377 expression, and miR-377 overexpression lessened ox-LDL-induced THP-1 cell injuries by degrading RAB22A level. In conclusion, circ-C16orf62 played a crucial role in the regulation of apoptosis, inflammation, oxidative stress and cholesterol accumulation in ox-LDL-treated human macrophages via mediating the miR-377/RAB22A axis, hinting that circ-C16orf62 might be involved in AS progression. [ABSTRACT FROM AUTHOR]

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Non-coding RNAs, especially microRNAs (miRNAs), play an important role in skeletal muscle growth and development. miR-377 regulates many basic biological processes and plays a key role in tumor cell proliferation, migration and apoptosis. Nevertheless, the function of miR-377 during skeletal muscle development and how it regulates skeletal muscle satellite cells (SMSCs) remains unclear. In the present study, we proposed to elucidate the regulatory mechanism of miR-377 in the proliferation and differentiation of bovine primary SMSCs. Our results showed that miR-377 can significantly inhibit the proliferation of SMSCs. In addition, we found that miR-377 can reduce myotube formation and restrain skeletal myogenic differentiation. Moreover, the results obtained from the biosynthesis and dual luciferase experiments showed that FHL2 was the target gene of miR-377. We further probed the function of FHL2 in muscle development and found that FHL2 silencing significantly suppressed the proliferation and differentiation of SMSCS, which is contrary to the role of miR-377. Furthermore, FHL2 interacts with Dishevelled-2 (Dvl2) to enable Wnt/β-catenin signaling pathway, consequently regulating skeletal muscle development. miR-377 negatively regulates the Wnt/β-catenin signaling pathway by targeting FHL2-mediated Dvl2. Overall, these findings demonstrated that miR-377 regulates the bovine SMSCs proliferation and differentiation by targeting FHL2 and attenuating the Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Nan Bu,1,* Zheng Dong,2,* Lingfeng Zhang,3 Weibo Zhu,4 Furong Wei,5 Sheng Zheng6 1Department of Gastroenterology, Chinese Medicine Hospital of Jiamusi City, Heilongjiang Province, Jiamusi, Heilongjiang, People’s Republic of China; 2Department of General Surgery, Ningbo Mingzhou Hospital, Ningbo, Zhejinag, People’s Republic of China; 3Department of Hepatobiliary Surgery, The First People’s Hospital of Huaihua City, Huaihua, Hunan, People’s Republic of China; 4Department of Medical Technology, Qujing Medical College, Qujing, Yunan, People’s Republic of China; 5Department of Gastroenterology, Central Hospital of Haining, Haining, Zhejinag, People’s Republic of China; 6Department of Gastroenterology, The Third People’s Hospital of Yunnan Province, Kunming, Yunnan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Sheng ZhengDepartment of Gastroenterology, The Third People’s Hospital of Yunnan Province, 292 Beijing Road, Guandu District, Kunming City, Yunnan Province, People’s Republic of ChinaTel +86-871-63196247Email x5z25a@163.comBackground: Recent studies reported that circular RNAs (circRNAs) exert essential functions in hepatocellular carcinoma (HCC) progression. However, the expression profile and function of circular RNA PVT1 (circPVT1) in HCC are not fully addressed. Thus, we aimed to probe into the function of circPVT1 in HCC development.Methods: The levels of circPVT1, microRNA-377 (miR-377) and transcripts encoding tripartite motif containing 23 (TRIM23) were determined by qRT-PCR. The stability and localization of circPVT1 were examined by RNase R digestion assay and subcellular fraction assay, respectively. Cell proliferation and apoptosis were evaluated by MTT assay and flow cytometry analysis, respectively. The relationship between miR-377 and circPVT1 or TRIM23 was determined by dual-luciferase reporter assay and RNA immunoprecipitation (RIP). The protein expression of TRIM23 was measured by Western blot. The glycolysis level was assessed by specific kits and Seahorse Extracellular Flux Analyzer XF96. The function of circPVT1 in vivo was investigated in a murine xenograft model.Results: CircPVT1 and TRIM23 levels were elevated, while miR-377 was decreased in HCC. CircPVT1 knockdown restrained proliferation and glycolysis, but enhanced apoptosis in HCC cells. CircPVT1 could bind to miR-377 and inhibition of miR-377 restored circPVT1 knockdown-mediated effect on HCC cells. TRIM23 was certified as a target of miR-377, and TRIM23 upregulation overturned the influence of miR-377 upregulation or circPVT1 silence on HCC progression. Moreover, circPVT1 knockdown restrained tumor growth in HCC in vivo.Conclusion: CircPVT1 aggravated the progression of HCC by upregulating TRIM23 via sponging miR-377.Keywords: hepatocellular carcinoma, circPVT1, miR-377, TRIM23

Background The interaction of long non-coding RNAs (lncRNAs)-microRNAs (miRs) exerts crucial functions in mediating inflammatory reaction. It is still unclear whether myocardial infarction associated transcript 2 (Mirt2)-miR-377 mediates the inflammatory pathogenesis in Sjögren's syndrome (SS).Methods The inflammatory lesion model was established by stimulating salivary gland epithelial cells (SGECs) by interferon gamma (IFN-γ). Mirt2- and/or miR-377-transfected SGECs, as well as their negative controls, were applied to investigate the biological functions in inflammation. Cell viability and apoptosis were examined using commercial kits. Western blot was applied to quantify protein level, and enzyme-linked immuno sorbent assay (ELISA) was used to value the secretion of cytokines.Results The up-regulation of Mirt2 was observed in IFN-γ-treated SGECs. Mirt2 overexpression restored the expression of miR-377 which was repressed by IFN-γ. However, miR-377 silence abolished the protective effect on cell viability, inhibitory effect on apoptosis and prohibitive role in pro-inflammatory factors. Mirt2 diminished the phosphorylated expression of crucial regulators while miR-377 silence restored the phosphorylation in IFN-γ-treated SGECs.Conclusion Mirt2 was elevated in IFN-γ-treated SGECs and then up-regulated miR-377 in response to inflammatory lesions. Mechanically, in synergy with miR-377 Mirt2 blocked IFN-γ-evoked activation of NF-κB and JAK/STAT signalling pathway.

Background: Chemoresistance remains a major obstacle to the treatment of esophageal cancer patients. Exosome-mediated transfer of circular RNAs (circRNAs) has been reported to be related to drug resistance in esophageal cancer. This study is designed to explore the role and mechanism of exosomal circ_0000337 on CDDP resistance in esophageal cancer.Methods: Cell viability, proliferation, colony number, apoptosis, migration, and invasion were assessed by Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, and transwell assays. Circ_0000337, microRNA-377 (miR-377-3p), and Janus kinase 2 (JAK2) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Exosomes were isolated and detected by differential centrifugation and a transmission electron microscope. Protein levels of CD9, CD63, and JAK2 were tested by Western blot assay. The binding relationship between miR-377-3p and circ_0000337 or JAK2 was predicted by circinteractome or Starbase and then verified by dual-luciferase reporter assay and RNA pull-down assay. The biological role of exosomal circ_0000337 and CDDP on esophageal cancer cell growth was examined by the xenograft tumor model in vivo.Results: Circ_0000337 and JAK2 were highly expressed, and miR-377-3p was decreased in CDDP-resistant esophageal cancer tissues and cells. Moreover, circ_0000337-containing exosomes secreted by CDDP-resistant esophageal cancer cells could promote CDDP resistance, cell growth, and metastasis in CDDP-sensitive esophageal cancer cells in vitro. The mechanical analysis discovered that circ_0000337 functioned as a sponge of miR-377-3p to regulate JAK2 expression. Exosomal circ_0000337 increased the drug resistance of esophageal cancer in vivo.Conclusion: Exosomal circ_0000337 accelerated CDDP resistance of esophageal cancer cells partly by regulating the miR-377-3p/JAK2 axis, hinting a promising therapeutic target for the esophageal cancer treatment.

Background: Diabetic peripheral neuropathy (DPN) is one of the most common and complex chronic complications of diabetes, but it is clinically lacking effective means for early diagnosis and early treatment. MicroRNA, in the occurrence and development of the disease, has an important regulatory role. Its role in diabetes has been reported more. However, specific research on microRNA in DPN is rare. Methods: Based on the results of bioinformatics screening, miR-377 and miR-216a, their respective target molecules growth association protein 43 (GAP-43) and angiopoietin-like 4 protein (ANGPTL4), and related pathways peroxisome proliferator activated receptor gamma (PPARG) and chemerin were tested by RT-qPCR and ELISA in blood samples of DPN to analyze the correlation between these differentially expressed molecules and clinico-pathological factors of DPN. Results: In this study, we found that miR-377, miR-216a, GAP-43, ANGPTL4, and PPARG were significantly differentially expressed genes for DPN. The correlation analysis showed that they were closely related to the clinical indicators of DPN suggesting that they may be involved in the development of DPN. In addition, receiver operating characteristic (ROC) curves generated for miR216a, miR377, ANGPTL4, GAP43, PPARG revealed that they can be used as new molecular diagnostic markers of DPN. Conclusions: miR-216a, miR-377, ANGPTL4, GAP-43, and PPARG could potentially be biomarkers of DPN. [ABSTRACT FROM AUTHOR]

The value of novel biomarkers for DKD has received increasing attention, and there is an urgent need for novel biomarkers with sensitivity, specificity and ability to detect kidney damage.miR-377 regulates many basic biological processes, plays a key role in tumor cell proliferation, migration and inflammation, and can also increase the expression of matrix proteins and fibronectin, leading to renal tubulointerstitial inflammation and renal fibrosis. Lipoprotein-associated phospholipase A2, as an inflammatory marker, is involved in the pathological process of microalbuminuria production and renal function decline, and is a predictive factor of microalbuminuria production and renal function decline, and can be used as an indicator to evaluate the progression of DKD.The aim of this study was to investigate the effects of miR-377 and phospholipase A2 on the development of diabetic kidney disease through regulation of inflammatory factors and the mechanism of action. Methods: 80 diabetic patients were divided into two groups according to urinary albumin-to-creatinine ratio (UACR): diabetic normal proteinuria group (n = 42) and diabetic proteinuria group (n = 38). Forty-three healthy people were selected as the normal control group. The serum levels of TGF-β, IL-6, and IL-18 were measured by ELISA, miR-377 was detected by qPCR, and the serum levels of phospholipase A2 were detected by electrochemiluminescence. Analyze the correlation of study group indicators, ROC curve was used to evaluate the diagnostic efficacy of miR-377 and phospholipase A2 in diabetic kidney disease. Results: The average levels of serum TGF-β, IL-6, IL-18, miR-377 and phospholipase A2 in diabetic proteinuria group were significantly higher than those in normal control group and diabetic proteinuria normal group(P < 0.05). miR-377, phospholipase A2 were significantly correlated with inflammatory factors such as glomerular filtration rate and TGF-β. miR-377 and phospholipase A2 are independent predictors of diabetic kidney disease. The area under the curve of miR-377 and phospholipase A2 in the normal diabetic proteinuria group and the diabetic proteinuria group were 0.731 and 0.744, respectively. Conclusion: miR-377 and phospholipase A2 have good diagnostic efficiency for the early diagnosis of diabetic kidney disease. They can be used as early biomarkers.miR-377 and phospholipase A2 were positively correlated with inflammatory factors and involved in the occurrence and development of diabetic kidney disease. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) have pivotal roles in regulating ischemic stroke (IS), including lncRNA rhabdomyosarcoma 2-associated transcript (RMST). The purpose of this report is to discover the functional mechanism of RMST. The expression detection of RMST, microRNA-377 (miR-377) and Semaphorin 3A (SEMA3A) was performed by quantitative real-time polymerase chain reaction (qRT-PCR). Oxygen and glucose deprivation/reperfusion (OGD/R) in N2a cells was used to mimic IS environment in vitro. Cell Counting Kit-8 (CCK-8) and flow cytometry were implemented to assess cell viability and apoptosis. Oxidative stress was analyzed via assaying the associated indicators. Dual-luciferase reporter, RNA pull-down and RNA immunoprecipitation (RIP) assays were jointly administrated for binding analysis between targets. SEMA3A protein level was measured using western blot. We found in IS serum samples, RMST was upregulated while miR-377 was downregulated. After the establishment of OGD/R-induced IS model, we found that the decreased RMST abrogated the OGD/R-triggered apoptosis and oxidative stress. Through the target analysis, miR-377 was shown to be sponged by RMST and the effects of RMST knockdown on OGD/R-induced cell injuries were related to miR-377 upregulation. Besides, SEMA3A served as a target gene of miR-377 and the mitigation of miR-377 for ischemic brain damages was achieved by downregulating SEMA3A. What's more, RMST could regulate SEMA3A by playing the sponge action on miR-377. Collectively, all these findings clarified that RMST repression retarded IS progression in vitro via SEMA3A downregulation by targeting miR-377, which represented a different perspective in the pathological development of IS. [ABSTRACT FROM AUTHOR]

The MYC gene is a regulatory and proto-oncogenic gene that is overexpressed in the majority of prostate cancers (PCa). Numerous studies have indicated that aberrant expression of microRNAs is involved in the initiation and progression of prostate cancer. In this investigation, we assessed the impact of miR-377 on MYC through luciferase assay. Real-time PCR was employed to determine whether miR-377 could reduce the levels of MYC mRNA in transfected PCa cell lines (PC-3 and DU145) and change in the mRNA levels of BCL-2/Bax, PTEN, and CDK4 as a consequence of MYC downregulation. Moreover, we analyzed the effects of miR-377 on apoptosis, proliferation, cell cycle, and wound healing. Our findings demonstrate that miR-377 effectively targets MYC mRNA, as confirmed by luciferase assay and Real-time PCR. We observed a significant reduction in BCL-2 and CDK4 expression, along with an increase in Bax and PTEN, in prostate cancer cell lines upon MYC suppression. Additionally, elevated levels of miR-377 in PCa cell lines induced apoptosis, inhibited proliferation and migration, and arrested the cell cycle. Taken together, these results unveil the inhibitory role of miR-377 in MYC function within PCa, thereby suggesting its potential as a therapeutic target for the treatment of this malignancy., Competing Interests: CONFLICTS OF INTEREST Authors have no conflicts of interest to declare.

Abstract Background The blood-brain barrier (BBB) strongly restricts the entry of anti-glioma drugs into tumor tissues and thus decreases chemotherapy efficacy. Malignant gliomas are highly invasive tumours that use the perivascular space for invasion and co-opt existing vessels as satellite tumor form. Because regulation of the effect of noncoding RNA on BBB function is attracting growing attention, we investigated the effects of noncoding RNA on the permeability of glioma conditioned normal BBB and the mechanism involved using PIWI-associated RNA piR-DQ590027 as a starting point. Methods The mRNA levels of MIR17HG, miR-153, miR-377, ZO-1, occludin, and claudin-5 were determined using real-time PCR. Transient cell transfection was performed using Lipofectamine 3000 reagent. TEER and HRP flux were applied to measure the permeability of glioma conditioned normal BBB. Western blotting and immunofluorescence assays were used to measure ZO-1, occludin, and claudin-5 levels. Reporter vector construction and a luciferase reporter assay were performed to detect the binding sites of MIR17HG and piR-DQ590027, MIR17HG and miR-153 (miR-377), and FOXR2 and miR-153 (miR-377). RNA immunoprecipitation was used to test the interaction between miR-153 (miR-377) and its target proteins. Chromatin immunoprecipitation was performed to detect the interaction between the transcription factor FOXR2 and ZO-1, occludin, and claudin-5. Results piR-DQ590027 was expressed at low levels in glioma-conditioned ECs (GECs) of the in vitro glioma conditioned normal BBB model. Overexpression of piR-DQ590027 down-regulated the expressions of ZO-1, occludin, and claudin-5 and increased the permeability of glioma conditioned normal BBB. MIR17HG had high expression in GECs but miR-153 and miR-377 had low expression. piR-DQ590027 bound to and negatively regulated MIR17HG. FOXR2 was a downstream target of miR-153 and miR-377; MIR17HG bound separately to miR-153 and miR-377 and negatively regulated their ability to mediate FOXR2 expression. FOXR2 associated with the promoter regions of ZO-1, occludin, and claudin-5 in GECs to promote their transcription. Conclusion The piR-DQ590027/MIR17HG/miR-153 (miR-377)/FOXR2 pathway plays an important role in regulating glioma conditioned normal BBB permeability and provides a new target for the comprehensive treatment of glioma.

Background: The dysregulation of the human papillomavirus 18 E6 and E7 oncogenes plays a critical role in the angiogenesis of cervical cancer (CC), including the proliferation, migration, and tube formation of vascular endothelial cells. Interfering E6/E7 increases the number of CC cell-derived microvesicles (CC-MVs). Additionally, microRNAs (miRNAs) can modulate CC angiogenesis and can be encapsulated in MVs. Objective: We aim to investigate whether E6/E7 affects CC angiogenesis via regulating miRNAs in CC-MVs. Methods: CC-MVs were isolated from a CC cell line (HeLa) which were transfected with small interfering RNAs (siRNAs) against E6/E7 or co-transfected with miR-377 mimics/inhibitors. The expression of several miRNAs in CC-MVs was detected using quantitative real-time PCR. After co-incubating CC-MVs with human umbilical vein endothelial cells (HUVECs), cell proliferation, migration, and tube formation of HUVECs were determined using cell counting kit-8, transwell, and tube formation assays, respectively. Results: MiR-377 was increased in E6/E7-interfering CC-MVs. Overexpressing miR-377 in CC-MVs suppressed HUVEC proliferation, migration, and tube formation. LPAR2, the cell surface G protein-coupled receptor, was the downstream target of miR-377 in HUVECs. The co-transfection of E6/E7 siRNAs and miR-377 inhibitors in CCs negated the effect of E6/E7 siRNAs on the elevation of miR-377 in CC-MVs. In HUVECs, the co-transfection of E6/E7 siRNAs and miR-377 inhibitors restored the LPAR2 expression which was reduced by the E6/E7 siRNA transfection. Meanwhile, miR-377 mimic reduced LPAR2 expression and inhibited HUVEC proliferation, migration, and tube formation, while such response was negated by LPAR2 overexpression. Conclusion: Interfering E6/E7 increased miR-377 in CC-MVs, and overexpressing miR-377 in CC-MVs inhibited angiogenesis of HUVECs via reducing LPAR2. [ABSTRACT FROM AUTHOR]

Difficult‐to‐express (DTE) recombinant proteins such as multi‐specific proteins, DTE monoclonal antibodies, and lysosomal enzymes have seen difficulties in manufacturability using Chinese hamster ovary (CHO) cells or other mammalian cells as production platforms. CHO cells are preferably used for recombinant protein production for their ability to secrete human‐like recombinant proteins with posttranslational modification, resistance to viral infection, and familiarity with drug regulators. However, despite huge progress made in engineering CHO cells for high volumetric productivity, DTE proteins like recombinant lysosomal sulfatase represent one of the poorly understood proteins. Furthermore, there is growing interest in the use of microRNA (miRNA) to engineer CHO cells expressing DTE proteins to improve cell performance of relevant bioprocess phenotypes. To our knowledge, no research has been done to improve CHO cell production of DTE recombinant lysosomal sulfatase using miRNA. We identified miR‐23a and miR‐377 as miRNAs predicted to target SUMF1, an activator of sulfatases, using in silico prediction tools. Transient inhibition of CHO endogenous miR‐23a/miR‐377 significantly enhanced recombinant sulfatase enzyme‐specific activity by ~15–21% compared to scramble without affecting cell growth. Though inhibition of miR‐23a/miR‐377 had no significant effect on the mRNA and protein levels of SUMF1, overexpression of miR‐23a/377 caused ~30% and ~27–29% significant reduction in endogenous SUMF1 protein and mRNA expression levels, respectively. In summary, our data demonstrate the importance of using miRNA to optimize the CHO cell line secreting DTE recombinant lysosomal sulfatase. [ABSTRACT FROM AUTHOR]

Background/Aims: Long noncoding RNAs (lncRNAs) have been demonstrated to serve distinct roles in human tumorigenesis. Previous studies have found that lncRNA small nucleolar RNA host gene 4 (SNHG4) was dysregulated in several tumors. However, the expression, clinical significances, and action mechanisms of SNHG4 in prostate cancer (PCa) are still unclear. Methods: Quantitative real‐time polymerase chain reaction (qRT‐PCR) was utilized to detect SNHG4 expression in tissue samples and PCa cells. Cell counting kit‐8, 5‐ethynyl‐2′‐deoxyuridine, clonogenic formation, wound‐healing, and transwell invasion assays were, respectively, used to evaluate cell proliferation, colony formation ability, migration, and invasion. Flow cytometric analysis was applied to assess cell apoptosis. Chromatin immunoprecipitation assays were conducted to determine the binding between SP1 and SNHG4 promoter. Luciferase reporter assay, qRT‐PCR, and western blot analysis were carried out to explore and confirm the interaction among SNHG4, miR‐377, and ZIC5. Results: SNHG4 was highly expressed in PCa and its upregulation was induced by transcription factor SP1. The high levels of SNHG4 were distinctly associated with tumor stage, lymph node metastasis, and reduced overall survival of patients with PCa. SNHG4 knockdown inhibited the growth, migration, and invasion of PCa cells. In addition, miR‐377 was a target of SNHG4 and ZIC5 was a target gene of miR‐377 in PCa. SNHG4 promoted ZIC5‐mediated growth and metastasis through modulating miR‐377. Conclusion: Our findings illuminate how SNHG4 formed a regulatory network to display a tumor‐promotive effect in PCa and revealed that SNHG4 may be a novel therapeutic target and prognostic marker for patients with PCa. [ABSTRACT FROM AUTHOR]

Background: miR-377 is closely related to myocardial regeneration. miR-377-adjusted mesenchymal stem cells abducted ischemic cardiac angiogenesis. Nevertheless, there were rarely reports about the impact of miR-377 on myocardial ischemia injury. The purpose of this work is that whether miR-377 can protect against myocardial injury caused by hypoxia/reoxygenation (H/R). Methods: Gene expression omnibus database (http://www.ncbi.nlm.nih.gov/geo/; no. GSE53211) was utilized to study the differential expression of miR-377 in patients with an acute ST-segment elevation myocardial infarction and healthy controls. The luciferase activity was determined utilizing the dual-luciferase reporter system. Quantitative real-time polymerase chain reaction and Western blotting were used to measure the messenger RNA and protein level. Results: Low expression of miR-377 and high expression of leukocyte immunoglobulin-like receptor B2 (LILRB2) were identified in patients with myocardial infarction from analyzing the Gene Expression Omnibus data set. Besides, miR-377 expression was downregulated in cardiomyocyte exposed to H/R. Additionally, overexpression of miR-377 could visibly improve cardiomyocyte injury by regulating cell activity and apoptosis. Conclusions: In short, our findings suggested that miR-377/LILRB2 might regard as a hopeful therapeutic target for myocardial ischemic. [ABSTRACT FROM AUTHOR]

CircPRTM5 is associated with cell proliferation and migration in many kinds of malignancies. However, the functions and mechanisms of CircPRTM5 in CRC progression remain unclear. We explored the role and the mechanisms of CircPRTM5 in the development of CRC. Tissues of CRC patients and matched adjacent non‐tumour tissues were collected to evaluate the expression of CircPRTM5. The expression of CircPRTM5 in CRC tissues was significantly higher than that in adjacent tissues. The biological functions of CircPRTM5 in CRC were determined by overexpression and down‐regulation of CircPRTM5 in CRC cells in vitro and in vivo. The results indicate that knockdown of CircPRTM5 can significantly inhibit the proliferation of CRC cells. The potential mechanisms of CircPRTM5 in CRC development were identified by RT‐qPCR, Western blotting analysis and luciferase reporter assay. CircPRTM5 competitively regulates the expression of E2F3 by capillary adsorption of miR‐377. CircPRMT5 regulates CRC proliferation by regulating the expression of E2F3, which affects the expression of the cell cycle‐associated proteins cyclinD1 and CDK2. CircPRTM5 exerts critical regulatory role in CRC progression by sponging miR‐377 to induce E2F3 expression. [ABSTRACT FROM AUTHOR]

Objective: To study the effect of MiR-377-mediated Syk on atherosclerosis in ApoE/mice. Methods: The experimental subjects were divided into control group (ApoE_/mice), MiR- 377 group (ApoE_/mice injected with MiR-377), Syk group (ApoE_/mice injected with Syk) and Syk+ MiR-377 group (ApoE_/mice injected with MiR-377and Syk). MiR-377 singlestranded antisense nucleotide drugs and Syk gene sequences were prepared and transfected into ApoE_/mice. The expression of Syk gene and protein in ApoE_/mice was detected by qPCR and Western blot, and the levels of inflammatory factors, lipid and oxidative dismutase were detected. The effects of MiR-377 on atherosclerotic aortic plaque and surface area in ApoE_/mice were studied by HE staining and oil red O staining. Results: The relative expression of Syk gene in MiR-377 group was significantly lower than that in control group, and the expression of Syk protein in MiR-377 group was significantly lower than that in control group. TNF-alpha levels in Syk group were significantly lower than those in control group and MiR-377 group. The 1L-6 level in the MiR-377 group was significantly higher than that in the control group, while the 1L-6 level in the Syk group and the MiR377+Syk group was significantly lower than that in the control group. The level of 1L-1ß in the MiR377 group was significantly lower than that in the control group. The TC level of MiR-377 group was significantly lower than that of control group, and the 1L-1ß level of Syk group was significantly higher than that of control group and MiR-377 group. The level of LDL in the MiR-377 group was significantly lower than that in the control group, the level of HDL in the MiR-377 group was significantly lower than that in the control group, and the level of HDL in the Syk group was significantly higher than that in the control group and the MiR-377 group. The level of SOD in the MiR-377 group was significantly higher than that in the control group. There were obvious aortic plaques in the control group and Syk group. There were no obvious aortic plaques in the MiR-377+Syk group and the MiR-377 treated group. The area of atherosclerotic plaque in ApoE_/mice treated with MiR-377 decreased significantly. The plaque area of ApoE-/- mice treated with Syk increased. The ratio of sclerotic plaque area to total area was 25.63% in control group, 7.81% in mi-377 group, 35.19% in Syk group and 9.73% in Syk + MiR-377 group. Conclusion: Overexpression of Syk gene can increase lipid accumulation and oxidative stress in atherosclerotic cells. Mir-377 can regulate the development of atherosclerosis by inhibiting the expression of Syk gene. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that cardiomyocyte autophagy is relevant to the onset of cardiac hypertrophy (CH). Several miRNAs are involved in the occurrence of heart failure, and relevant therapeutic treatments are currently being developed. MicroRNA-377 (miR-377) is known to correlate with the progression of various cancers, however, its function in CH has not been determined. Therefore, this study aimed to evaluate miR-377 expression in H2C9 hypertrophic cardiomyocytes in vitro and in a murine model of CH. Gene expression changes were verified via qRT-PCR. Western blotting was used for evaluation of alterations in the expression of signaling pathway-related proteins. Our results indicated that miR-377 expression was markedly upregulated in mice with hypertrophic cardiomyopathy. Autophagy markers were downregulated in these mice and in hypertrophic cardiomyocytes following miR-377 transfection. In addition, we demonstrated that miR-377 acts by targeting peroxisome proliferator-activated receptor γ (PPARγ). PPARγ overexpression promoted autophagy and suppressed cyclosporine A-induced CH. In contrast, PPARγ knockdown further suppressed CH and autophagy. In conclusion, our findings indicated that miR-377 accelerates CH by inhibiting autophagy via targeting PPARγ. This newly identified miR-377/PPARγ axis improves our understanding of the molecular mechanisms underlying CH, and provides a potential new therapeutic target for its treatment. [ABSTRACT FROM AUTHOR]

Introducción: El estrés oxidativo ha sido implicado en el desarrollo y la progresión de la calcificación vascular (CV); sin embargo, aún existen interrogantes sobre esta asociación causal. Objetivo: Analizar en un modelo experimental de insuficiencia renal crónica (IRC) el efecto del estrés oxidativo sobre el desarrollo y la progresión de la CV, evaluando la implicación del microARN-377 (miR-377). Material y métodos: Se estudiaron 2 grupos de ratas Wistar con IRC. El grupo 1 recibió dieta normal en fósforo (IRC+PN). El grupo 2 recibió dieta con alto fósforo (IRC+PA). Se incluyó un grupo de ratas Sham. Trascurridas 20 semanas, las ratas fueron sacrificadas. Resultados: El fósforo y la parathormona séricos no aumentaron en el grupo IRC+PA respecto al IRC+PN, pero sí los niveles de factor de crecimiento fibrobástico 23 (FGF23). En el grupo IRC+PN aumentó tres veces el contenido aórtico de calcio respecto al grupo Sham, un aumento 17 veces superior en el grupo IRC+PA, donde la densidad mineral ósea en tibia proximal descendió significativamente. En el grupo IRC+PN la expresión del miR-377 disminuyó un 65%, sin efecto adicional de la dieta con alto contenido en fósforo. En el grupo IRC+PN aumentó 3 veces la expresión proteica de superóxido dismutasa 2 mitocondrial (SOD-2), y en el grupo IRC+PA lo hizo hasta 6 veces. Conclusiones: La IRC con o sin alto contenido en fósforo en la dieta desencadenó el descenso del miR-377. El exceso de fósforo incrementó la SOD-2 como mecanismo compensador para frenar el estrés oxidativo y el daño vascular. Controlar el contenido en fósforo en la dieta cuando la función renal se ve comprometida permitirá aminorar el daño vascular producido como consecuencia, entre otros factores, del estrés oxidativo.

Background: The interaction of long non-coding RNAs (lncRNAs)-microRNAs (miRs) exerts crucial functions in mediating inflammatory reaction. It is still unclear whether myocardial infarction associated transcript 2 (Mirt2)-miR-377 mediates the inflammatory pathogenesis in Sjögren's syndrome (SS). Methods: The inflammatory lesion model was established by stimulating salivary gland epithelial cells (SGECs) by interferon gamma (IFN-γ). Mirt2- and/or miR-377-transfected SGECs, as well as their negative controls, were applied to investigate the biological functions in inflammation. Cell viability and apoptosis were examined using commercial kits. Western blot was applied to quantify protein level, and enzyme-linked immuno sorbent assay (ELISA) was used to value the secretion of cytokines. Results: The up-regulation of Mirt2 was observed in IFN-γ-treated SGECs. Mirt2 overexpression restored the expression of miR-377 which was repressed by IFN-γ. However, miR-377 silence abolished the protective effect on cell viability, inhibitory effect on apoptosis and prohibitive role in pro-inflammatory factors. Mirt2 diminished the phosphorylated expression of crucial regulators while miR-377 silence restored the phosphorylation in IFN-γ-treated SGECs. Conclusion: Mirt2 was elevated in IFN-γ-treated SGECs and then up-regulated miR-377 in response to inflammatory lesions. Mechanically, in synergy with miR-377 Mirt2 blocked IFN-γ-evoked activation of NF-κB and JAK/STAT signalling pathway. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is one of the common microvascular complications of diabetes mellitus, which is the main cause of blindness in diabetic patients. Angiogenesis plays an important role in retinal detachment and retinal microvascular inflammation throughout the whole development of DR. This study aimed to investigate the regulatory effect and the potential mechanism of miR-377 on high glucose and hypoxia-induced angiogenesis and inflammation in human retinal endothelial cells, and found that the miR-377 level was significantly increased after high glucose and hypoxia-mimetic agent to simulate the DR milieu. Moreover, miR-377 was confirmed to directly decrease target SIRT1 gene, further aggravated proliferation, cell cycle transition, migration and angiogenesis, pro-inflammatory molecules release induced by high glucose and hypoxia in vitro. Conversely, down-regulation of miR-377 enhanced expression of SIRT1 and in turn alleviated high glucose and hypoxia-induced angiogenesis and inflammation in vitro. Additionally, Western blot results showed that down-regulation of miR-377 restrained high glucose and hypoxia-induced protein expressions of p-IκBα, nuclear P65 and p-P65. Conversely, up-regulation of miR-377 presented opposite results. Conclusively, down-regulation of miR-377 could partially suppress high glucose and hypoxia-induced angiogenic functions, restrain pro-inflammatory cytokines release, and its mechanism may though inhibition of NF-κB pathway by direct up-regulation of target gene SIRT1 expression. Our study suggests that miR-377 may be used as a potential novel target for prevention strategy for DR. [ABSTRACT FROM AUTHOR]

Periprosthetic osteolysis caused by wear particles is the main factor that affects the long‐term efficacy of artificial joint replacement, and macrophages play a vital role in the pathogenesis of periprosthetic osteolysis, while the potential mechanism underlying this is still unclear. To investigate the underlying role of miR‐377 in wear particle‐induced osteolysis (PIO), blood samples from patients undergoing arthroplasty were collected for analyzing the correlation between miR‐377 expression and the clinicopathological parameters of PIO. Peripheral blood macrophages were obtained to compare the miR‐377 and receptor activator of NF‐κB ligand (RANKL) expressions. Bone marrow macrophages (BMMs) following titanium (Ti) particle treatment and/or miR‐377 mimic transfection were used. The expressions of RANKL, pro‐inflammatory cytokines interleukin 6 (IL‐6) and tumor necrosis factor‐α (TNF‐α) and the osteoclast‐related molecules tartrate‐resistant acid phosphatase (TRAP) and cathepsin K (CTSK) were determined using real‐time polymerase chain reaction or western blotting or enzyme‐linked immunosorbent assay or TRAP staining, when appropriate. The interaction between miR‐377 and RANKL was assessed by luciferase reporter assay. The in vivo role of miR‐377 in PIO was evaluated using a mouse calvarial osteolysis model. There were significant differences in downregulated miR‐377 expression between the different numbers of particles in the joint prostheses. The Ti particle treatment increased pro‐inflammatory cytokine levels, downregulated RANKL and increased osteoclast activity in BMMs, while miR‐377 overexpression led to the opposite effect. Taken together, miR‐377 downregulated the target gene RANKL, resulting in PIO inhibition. MiR‐377 relieved PIO by negatively regulating RANKL. [ABSTRACT FROM AUTHOR]

Highlights • lncRNA NEAT1 protects BMEC from OGD induced injury. • lncRNA NEAT1 facilitates angiogenesis in OGD induced BMEC. • lncRNA exhibits protective effect via targeting miR-377 and uprelating VEGFA, SIRT1, BCL-XL. Abstract Objective The present study was designed to investigate the mechanism by which lncRNA NEAT1 regulates survival and angiogenesis in oxygen-glucose deprivation (OGD)-induced brain microvascular endothelial cells (BMECs). Methods OGD-treated BMECs were used to mimic cerebral ischaemia in vitro. The expression of lncRNA NEAT1 and miR-377 and proteins including VEGFA, SIRT1, and BCL-XL were measured by real-time quantitative PCR (qRT-PCR) and western blot, respectively. Cell viability and caspase 3 activity of BMECs under different conditions were determined using MTT and caspase activity assays, respectively. Matrigel-based angiogenesis assays were employed to evaluate the effect of lncRNA NEAT1 on angiogenesis. A dual-luciferase reporter assay was used to validate direct binding of miR-377 to putative targets. Results OGD exposure reduced the cell viability of BMECs. Upregulation of lncRNA NEAT1 and downregulation of miR-377 were also observed under OGD conditions. Knockdown of lncRNA NEAT1 inhibited angiogenesis and aggravated apoptosis in OGD-induced BMECs. Meanwhile, the expression level of miR-377 was upregulated while its downstream targets (VEGFA, SIRT1, and BCL-XL) were downregulated after lncRNA NEAT1 knockdown. Furthermore, miR-377 inhibited the angiogenesis and survival of OGD-induced BMECs. The expression of VEGFA, SIRT1, and BCL-XL were all attenuated by miR-377 overexpression. The dual-luciferase reporter assay proved miR-377 targeted the 3′ UTR sequences of lncRNA NEAT1, VEGFA, SIRT1, and BCL-XL. Conclusion lncRNA NEAT1 facilitated the survival and angiogenesis of OGD-induced BMECs via targeting miR-377 and promoting the expression of VEGFA, SIRT1, and BCL-XL, suggesting that lncRNA NEAT1 could be a promising target for cerebral ischaemia treatment. [ABSTRACT FROM AUTHOR]

Highlights • NF-κB and MAPK signaling are activated by renal I/R. • VEGF depletion by siRNA completely abrogates the impact of miR-377 on renal I/R-induced oxidative stress. • I/R stimulates miR-377 expression. Abstract MicroRNAs (miRNAs) play important roles in kidney development and maintenance of kidney physiological functions. MiR-377 has been reported to regulate inflammation in cardiac and cerebral ischemia. However, it remains unclear whether it has a similar function in renal ischemia/reperfusion (I/R). Using I/R model mice, miR-377 expression was determined by qRT-PCR in the renal tissues. Renal function was assessed by detection of the concentrations of blood urea nitrogen (BUN) and serum creatinine (Cr). Oxidative stress was evaluated by ELISA analysis of oxidation-related enzymes and molecules. Inflammatory factor concentration and other protein levels were analyzed by the ELISA assay and Western blot, respectively. Our study found that renal I/R stimulated miR-377 expression, while the inhibition of miR-377 attenuated renal I/R injury, and blocked renal I/R-induced oxidative stress and inflammation. Meantime, NF-κB and MAPK signaling were activated by renal I/R, which could also be reversed by miR-377 inhibitor. Furthermore, vascular endothelial growth factor (VEGF) depletion by siRNA completely abrogated the impact of miR-377 on renal I/R-induced oxidative stress, inflammation and renal dysfunction. In conclusion, renal I/R induced miR-377 expression, which upregulated VEGF expression to attenuate renal I/R-induced oxidative stress and inflammation, and finally ameliorated renal dysfunction. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Chemoresistance is one of the obstacles for effective treatment of cancers, and recent evidence has shown that microRNAs play critical roles in drug resistance. In this study, we investigated the effect of miR-377 on cisplatin resistance in osteosarcoma (OS). PATIENTS AND METHODS: Tumor tissues from chemoresistant and control OS patients were subjected to Real-time polymerase chain reaction (PCR) to assess miR-377 expression. The effect and mechanism of miR-377 on cisplatin resistance were assessed using Cell Counting Kit (CCK) 8, flow cytometry, Western blot, and luciferase assays in cisplatin-resistant OS cells lines. RESULTS: Down-regulation of miR-377 was found in chemoresistant OS tissues and cisplatin resistant OS cell lines. Overexpression of miR-377 re-sensitizes cisplatin-resistant OS cells to cisplatin-induced caspase-3 dependent apoptosis. MiR-377 directly represses X-linked inhibitor of apoptosis protein (XIAP) expression through binding to its 3' untranslated region (UTR) of mRNA. Overexpression of XIAP partially cancelled the cisplatin-sensitizing effect of miR-377. CONCLUSIONS: These data uncovered an essential function of miR-377/XIAP signaling axis in regulating cisplatin resistance of OS. MiR-377 may have potential therapeutic values in tackling OS chemoresistance. [ABSTRACT FROM AUTHOR]

OBJECTIVE: In recent years, microRNAs have been identified to participate in tumor genesis and progression of different tumors including gastric cancer. However, the role of miR-377 played in gastric cancer (GC), and its mechanisms have not been demonstrated. PATIENTS AND METHODS: We detected miR-377 expression level in 86 GC and adjacent normal tissue samples by quantitative reverse transcription PCR (qRT-PCR) as well as in GC cell lines. The relationship between miR-377 and clinical pathological features was analyzed. Using miR-377 mimics and inhibitors, we interfered with miR-377 level and employed several functional experiments to study the miR-377 effects on cell proliferation, migration, and invasion. Western blot assay and dual-luciferase assay were used to verify the target of miR-377. RESULTS: miR-377 expressed significantly lower in GC tissues and cell lines compared to normal tissues and GES-1 cells. Overexpression of miR-377 inhibited cell growth, migration and invasion, while downregulation miR-377 obviously promoted cell growth and metastasis. Furthermore, vascular endothelial growth factor A (VEGFA) was confirmed as a direct target of miR-377 and reversed the influence of mir-377 over-expression. CONCLUSIONS: miR-377 expressed lower in GC and suppressed cell proliferation, migration and invasion partly via repressing the VEGFA expression, which could provide a potential target for GC diagnosis and therapy. [ABSTRACT FROM AUTHOR]

Introduction: Oxidative stress has been implicated in the development and progression of vascular calcification (VC). However, this causal association remains a matter of controversy. Objective: To analyze in an experimental model of chronic renal failure (CRF), the effect of oxidative stress on the development and progression of the VC, assessing the implication of microRNA-377 (miR-377). Material and methods: Two groups of Wistar rats with CRF were studied. Group 1 received normal diet in phosphorus (CRF+NP). Group 2 received a high phosphorus (CRF+HP) diet. A group of sham rats was included. After 20 weeks, the rats were sacrificed. Results: Serum phosphorus and parathormone did not increase in the CRF+HP group compared to CRF+NP, but fibroblast growth factor 23 (FGF23) levels significantly increased. In the CRF+NP group, aortic calcium content increased three-fold over the sham group, a 17-fold increase in the CRF+HP group, where the bone mineral density in the proximal tibia decreased significantly. In the IRC+NP group, the expression of miR-377 decreased by 65%, with no additional effect detected of the diet with high phosphorus content. In the IRC+NP group, the protein expression of mitochondrial superoxide dismutase 2 (SOD-2) increased 3-fold, and in the IRC+HP group it increased up to 6-fold. Conclusions: CRF, with or without high phosphorus dietary content, triggered the descent of miR-377. Excess phosphorus increased SOD-2 as a compensatory mechanism to curb oxidative stress and vascular damage. Controlling phosphorus content in the diet when the renal impairment function is compromised will reduce the vascular damage produced due oxidative stress, among other factors. [ABSTRACT FROM AUTHOR]

Introduction: Oxidative stress has been implicated in the development and progression of vascular calcification (VC). However, this causal association remains a matter of controversy. Objective: To analyze in an experimental model of chronic renal failure (CRF), the effect of oxidative stress on the development and progression of the VC, assessing the implication of microRNA-377 (miR-377). Material and methods: Two groups of Wistar rats with CRF were studied. Group 1 received normal diet in phosphorus (CRF+NP). Group 2 received a high phosphorus (CRF+HP) diet. A group of Sham rats was included. After 20 weeks, the rats were sacrificed. Results: Serum phosphorus and parathormone did not increase in the CRF+HP group compared to CRF+NP, but fibroblast growth factor 23 (FGF23) levels significantly increased. In the CRF+NP group, aortic calcium content increased three-fold over the Sham group, a 17-fold increase in the CRF+HP group, where the bone mineral density in the proximal tibia decreased significantly. In the CRF+NP group, the expression of miR-377 decreased by 65%, with no additional effect detected of the diet with high phosphorus content. In the CRF+NP group, the protein expression of mitochondrial superoxide dismutase 2 (SOD-2) increased 3-fold, and in the CRF+HP group it increased up to 6-fold. Conclusions: CRF, with or without high phosphorus dietary content, triggered the descent of miR-377. Excess phosphorus increased SOD-2 as a compensatory mechanism to curb oxidative stress and vascular damage. Controlling phosphorus content in the diet when the renal impairment function is compromised will reduce the vascular damage produced due oxidative stress, among other factors. [ABSTRACT FROM AUTHOR]

Aberrantly expressed microRNAs (miRNAs/miRs) and their role in cancer development have recently gained more attention. However, the potential role of miRNAs in hepatocellular carcinoma (HCC) remains largely unknown. In this study, we demonstrated that miR-377 was markedly downregulated in HCC cell lines and primary human HCC tissues. The decreased expression of miR-377 contributes to the upregulation of Bcl-xL expression by targeting its 3-untranslated region (3-UTR). Functionally, knockdown of miR-377 noticeably increased HCC cell growth and colony formation and inhibited apoptosis. In contrast, overexpression of miR-377 suppressed cell proliferation and increased apoptosis. This study provides new insights for the use of miR-377 as a potential molecular target in HCC therapy. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study is aimed to investigate the cellular role of miR-377 and demonstrate that miR-377 negatively regulated cyclin-dependent kinase 6(CDK6) in human nonsmall cell lung cancer (NSCLC) cells. MATERIALS AND METHODS: qRT-PCR was performed to identify the miR-377 expression level in 45 paired NSCLC and adjacent normal lung tissues. Cell proliferation was measured by MTT. Apoptosis was detected by flow cytometric analysis. Luciferase reporter assays were employed to validate regulation of a putative target of miR-377. The effect of miR-377 on endogenous levels of this target was subsequently confirmed viaWestern blot. RESULTS: We found that the expression level of miR-377 was significantly reduced in NSCLC tissues and cell lines. On the contrary, CDK6 expression level was up-regulated in NSCLC tissues and cell lines. Based on Luciferase reporter assays, we confirmed that CDK6 was a direct target gene of miR-377. In vitro studies demonstrated that miR-377 overexpression reduced NSCLC cell proliferation and promoted apoptosis. CONCLUSIONS: Our discovery suggested that miR-377 might be used as a therapeutic reagent for the treatment of NSCLC in the future. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play important roles in the regulation of various tumor biological processes including proliferation and apoptosis. MiR-377 has been implicated in many types of cancer, whereas its expressional feature and potential biological function in pancreatic ductal adenocarcinoma (PDAC) remains unclear. In this study, we scanned the global miRNA expression profiles in PDAC from The Cancer Genome Atlas (TCGA) and found miR-377 was down-regulated significantly in PDAC. Then, its expression was measured in both pancreatic cancer tissues and cells; the data showed that miR-377 was de-regulated and inversely correlated with pathologic parameters of tumor growth or metastasis. We generated PDAC cell lines with stable overexpression or inhibition of miR-377, and our results indicated that miR-377 up-regulation significantly promoted cell viability, proliferation, and migration in PDAC cells, and also induced cell apoptosis and cell cycle arrest simultaneously. Binding-site predictions by bioinformatics showed that Pim-3 might be a potential target of miR-377. Luciferase reporter assay ulteriorly identified that miR-377 suppressed Pim-3 expression by binding the 3′-UTR. In tumor tissues, we also showed that the Pim-3 expression was inversely correlated with that of miR-377. Furthermore, stable ectopic miR-377 expression in pancreatic cancer cell lines suppressed Pim-3 expression, leading to the attenuation of Bad phosphorylation level at its Ser and promoting cell apoptosis. Overall, these results reveal that miR-377 may have tumor growth suppression function by down-regulating Pim-3 kinase expression to inhibit both pancreatic tumor growth and migration, and induce cell apoptosis. Hence, miR-377 may be a potential diagnostic marker and therapeutic target. [ABSTRACT FROM AUTHOR]

Background: BCL-xL is an anti-apoptotic BCL-2 family protein that inhibits apoptosis and is overexpressed in many cancers. We have reported that acquired resistance to the BCL-2 inhibitor ABT-199 (venetoclax) is associated with increased BCL-xL expression. Yet, how BCL-xL mediates chemoresistance in hematopoietic malignancies is not clear. This finding may help in design of new strategies for therapeutic intervention to overcome acquired chemoresistance mediated by BCL-xL. Results: We now show that the increased BCL-xL expression was inversely correlated with that of miR-377 in ABT-199-resistant cells. This finding was also extended to a panel of B-cell lymphoid lines and primary chronic lymphocytic leukemia (CLL) cells. miR-377 suppressed BCL-xL expression by recognizing two binding sites in the BCL-xL 3'-UTR. Mutation of these two miR-377 consensus-binding sites completely abolished its regulatory effect. Expression of a miR-377 mimic downregulated BCL-xL protein expression and significantly increased apoptotic cell death. Expression of a miR-377 inhibitor restored BCL-xL protein expression and limited cell death caused by the hypomethylating agent 5-azacytidine. Thus, miR-377-dependent BCL-xL regulation drives acquired therapeutic resistance to ABT-199. We further show that CLL patients who received a diverse array of chemotherapy regimens also had significantly higher BCL-xL and lower miR377 expression, indicating that exposure to chemotherapy might trigger transcriptional silencing of miR-377, which results in high levels of BCL-xL. Importantly, CLL patients with high BCL-xL/low miR-377 expression had an advanced tumor stage. Moreover, the high BCL-xL expression correlated with short treatment-free survival in 76 CLL patients. miR-377 is located at 14q32 in the DLK1-DIO3 region, which encodes the largest tumor suppressor miRNA cluster in humans. Examination of five additional 14q32 miRNAs revealed that the majority were significantly down-regulated in most CLL patients as well as in ABT-199-resistant cell lines. Remarkably, four of these miRNAs had significantly decreased expression in chemotherapy-treated CLL patients as compared to those untreated. These findings indicate a reduced expression of multiple miRNAs that may reflect a global silencing of this miRNA cluster in therapy-resistant lymphoid cells. Conclusions: These findings reveal a novel mechanism by which down-regulation of miR-377 increases BCL-xL expression, promoting chemotherapy resistance in B-cell lymphoid malignancies. [ABSTRACT FROM AUTHOR]

High dietary fructose is an important causative factor in the development of metabolic syndrome-associated glomerular podocyte oxidative stress and injury. Here, we identified microRNA-377 (miR-377) as a biomarker of oxidative stress in renal cortex of fructose-fed rats, which correlated with podocyte injury and albuminuria in metabolic syndrome. Fructose feeding increased miR-377 expression, decreased superoxide dismutase (SOD) expression and activity, and caused O 2 − and H 2 O 2 overproduction in kidney cortex or glomeruli of rats. This reactive oxygen species induction increased p38 MAPK phosphorylation and thioredoxin-interacting protein (TXNIP) expression and activated the NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome to produce interleukin-1β in kidney glomeruli of fructose-fed rats. These pathological processes were further evaluated in cultured differentiated podocytes exposed to 5 mM fructose, or transfected with miR-377 mimic/inhibitor and TXNIP siRNA, or co-incubated with p38 MAPK inhibitor, demonstrating that miR-377 overexpression activates the O 2 − /p38 MAPK/TXNIP/NLRP3 inflammasome pathway to promote oxidative stress and inflammation in fructose-induced podocyte injury. Antioxidants pterostilbene and allopurinol were found to ameliorate fructose-induced hyperuricemia, podocyte injury, and albuminuria in rats. More importantly, pterostilbene and allopurinol inhibited podocyte miR-377 overexpression to increase SOD1 and SOD2 levels and suppress the O 2 − /p38 MAPK/TXNIP/NLRP3 inflammasome pathway activation in vivo and in vitro, consistent with the reduction of oxidative stress and inflammation. These findings suggest that miR-377 plays an important role in glomerular podocyte oxidative stress, inflammation, and injury driven by high fructose. Inhibition of miR-377 by antioxidants may be a promising therapeutic strategy for the prevention of metabolic syndrome-associated glomerular podocyte injury. [ABSTRACT FROM AUTHOR]

Clear cell renal cell carcinoma (ccRCC) is the most common form of neoplasm occurring in the adult kidney. Although significant advances have been made in treatment for ccRCC, a significant percent of patients have no benefit from currently available treatment option. MicroRNAs (miRNAs) have been reported to play central roles in regulating tumor progression, and are being explored as potentially more effective therapies and diagnostic tools for various cancers. The transcription factor E26 transformation specific-1 (ETS1) is believed to be intimately involved in tumor progression, and is frequently upregulated in tumors, including ccRCC. However, few studies have investigated the implications of ETS1 in ccRCC, and no studies have investigated the dysregulated mechanisms responsible for aberrant ETS1 expression in ccRCC. We used databases, clinical samples and target prediction algorithms to investigate aberrant miR-377 expression and potential targets in ccRCC. Our results indicate that miR-377 is downregulated in ccRCC, and that miR-377 can regulate the expression of ETS1. Further, using cell cycle analysis, MTT, luciferase and knockdown experiments, we found evidence to suggest that ETS1 is central in the development of the proliferative, metastatic and invasive phenotype of ccRCC cells. Furthermore, miR-377 was found to directly downregulate the expression of ETS1 and reduce the ability of ccRCC cells to proliferate, migrate and invade. As miR-377 was found to be differentially expressed in ccRCC, and in light of the apparent central role of ETS1 in tumor development, our results indicate that miR-377 could be useful for ccRCC diagnostics, prognostics and therapeutics. [ABSTRACT FROM AUTHOR]

A large number of circular RNAs (circRNAs) are dysregulated in lung cancer and affect the progression and prognosis of lung disease. Herein, this study selected specific circular RNA (circ&#95;0070659) by bioinformatics analysis and aimed to investigate the role of circ&#95;0070659 in non-small cell lung cancer (NSCLC). The differentially expressed circRNA (hsa&#95;circ&#95;0070659) in NSCLC was screened from public databases (GEO), and real-time quantitative polymerase chain reaction (RT-qPCR) was carried out to identify the circ&#95;0070659 levels in cancer tissues and cells. NSCLC cell proliferation, migration, and invasion abilities after circ&#95;0070659 silencing was detected by colony formation assay, Cell Counting Kit-8 (CCK-8) assay and Transwell assay. Targeted binding between microRNA-377 (miR-377) and circ&#95;0070659 or Ras-Associated Binding Protein 3C (RAB3C) was verified by western blot, dual-luciferase reporter assay, and RNA pull-down assay. Our experimental results showed that circ&#95;0070659 levels were largely increased in tumor tissues and cells. Biologically, knockdown of circ&#95;0070659 obviously inhibited proliferation, migration, and invasion of NSCLC cells. Mechanistically, circ&#95;0070659 promoted RAB3C-mediated proliferation and invasion through sponging miR-377. Furthermore, miR-377 inhibitor reversed the inhibitory ability of circ&#95;0070659 silencing on malignant biological behavior of NSCLC cells. Our study revealed a novel signaling pathway that circ&#95;0070659/miR-377/RAB3C axis regulates tumor progression, and it may become a new therapeutic target for NSCLC.

Background: Chemoresistance remains a major obstacle to the treatment of esophageal cancer patients. Exosome-mediated transfer of circular RNAs (circRNAs) has been reported to be related to drug resistance in esophageal cancer. This study is designed to explore the role and mechanism of exosomal circ&#95;0000337 on CDDP resistance in esophageal cancer. Methods: Cell viability, proliferation, colony number, apoptosis, migration, and invasion were assessed by Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, and transwell assays. Circ&#95;0000337, microRNA-377 (miR-377-3p), and Janus kinase 2 (JAK2) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Exosomes were isolated and detected by differential centrifugation and a transmission electron microscope. Protein levels of CD9, CD63, and JAK2 were tested by Western blot assay. The binding relationship between miR-377-3p and circ&#95;0000337 or JAK2 was predicted by circinteractome or Starbase and then verified by dual-luciferase reporter assay and RNA pull-down assay. The biological role of exosomal circ&#95;0000337 and CDDP on esophageal cancer cell growth was examined by the xenograft tumor model in vivo . Results: Circ&#95;0000337 and JAK2 were highly expressed, and miR-377-3p was decreased in CDDP-resistant esophageal cancer tissues and cells. Moreover, circ&#95;0000337-containing exosomes secreted by CDDP-resistant esophageal cancer cells could promote CDDP resistance, cell growth, and metastasis in CDDP - sensitive esophageal cancer cells in vitro . The mechanical analysis discovered that circ&#95;0000337 functioned as a sponge of miR-377-3p to regulate JAK2 expression. Exosomal circ&#95;0000337 increased the drug resistance of esophageal cancer in vivo . Conclusion: Exosomal circ&#95;0000337 accelerated CDDP resistance of esophageal cancer cells partly by regulating the miR-377-3p/JAK2 axis, hinting a promising therapeutic target for the esophageal cancer treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zang, Qiu, Song and Wang.)